An antenna has multiple antenna elements, with a beam forming Butler matrix, having antenna ports and input/output ports, with each of said antenna elements being connected to a respective port of the beam forming Butler matrix. Transceiver circuitry is connected to each of the input/output ports of the beam forming matrix by means of respective distinct transmit and receive paths and a respective duplexer. Individually controllable gain control elements are located in each of the transmit and receive paths. These can be controlled in response to signal strength measurements made by the antenna.